View clinical trials related to Atrial Fibrillation Chronic.
Filter by:Atrial fibrillation is the most common heart arrhythmia with a prevalence of approximately 2% in the western world. Atrial fibrillation is associated with an increased risk of death and morbidity. The comparable effects of a lenient rate control strategy and a strict rate control strategy in patients with atrial fibrillation are uncertain and only one trial has assessed this previously in patients with permanent atrial fibrillation. The investigators will therefore undertake a randomised, superiority trial at four hospitals in Denmark.
Catheter ablation is an established cornerstone of therapy for patients with symptomatic atrial fibrillation (AF) who wish to avoid anti-arrhythmic drug therapy or for whom anti-arrhythmics have proven ineffective. Pulmonary vein isolation (PVI), in which circumferential ablation is performed around the ostia of the pulmonary vein - left atrial junctions, is the standard ablation approach internationally. Single-procedure success rates (1y, freedom from AF, off anti-arrhythmics) for patients with paroxysmal AF is roughly 70%, and even worse (roughly 50%) for patients with persistent AF. A number of strategies have been developed to improve outcomes in patients undergoing AF ablation, particularly in patients with persistent AF. Unfortunately, large prospective randomized trials (including STAR-AF II, published in NEJM in 2015) have demonstrated a failure of ancillary ablation techniques to improve AF ablation outcomes relative to PVI alone. In a collaborative effort between the Cardiology electrophysiology group and the Trayanova laboratory (Biomechanical Engineering), investigators have developed a strategy of patient-specific modeling to identify pro-arrhythmic sites in AF patients that may be amenable to ablation. In this approach, patients undergo a pre-ablation cardiac MRI with late gadolinium enhancement, to delineate regions of healthy atrial tissue and regions of scar (this scan is clinically indicated, and performed currently in patients undergoing PVI for AF). A novel in silico modeling to determine regions supporting electrical reentry in the atrium, driving ongoing AF, has been developed by the Trayanova lab. In preliminary studies, investigators have demonstrated the ability to identify and target these regions with catheter ablation in patients undergoing PVI. Investigators would like to conduct a prospective, randomized clinical trial in patients undergoing ablation for symptomatic persistent AF. All patients enrolled would undergo standard pre-procedure imaging (LGE-MRI) prior to the day of procedure. Investigators have developed methodology termed OPTIMA (OPtimal Target Identification via Modeling of Arrhythmogenesis) to determine, based on non-invasive patient-specific anatomic and tissue data from late gadolinium enhancement cardiac MRI (LGE-CMR) and simulation of cardiac electrical function, personalized ablation targets for persistent AF in patients with fibrotic remodeling.. Patients would be randomized to receiving PVI only versus PVI + OPTIMA ablation at the time of ablation. Patients would then be followed in standard clinical fashion at 3m, 6m, and 12m to assess for ablation efficacy and for procedural complications. Investigators postulate a 20% improvement in freedom from AF with PVI + OPTIMA ablation form 50% to 70% (compared to PVI alone), investigators anticipate that in 1:1 randomization, a sample size of 80 patients in each arm will yield a power calculation of 80% with an alpha of 0.05. Investigators anticipate that enrollment and 1y clinical follow-up for 160 patients (total) undergoing AF ablation will require a 4y timeline.